Phosphorus

White phosphorus exposed to air glows in the dark
The tetrahedral structure of P4O10 and P4S10.
A stable diphosphene, a derivative of phosphorus(I).
Robert Boyle
Guano mining in the Central Chincha Islands, ca. 1860.
Mining of phosphate rock in Nauru
Match striking surface made of a mixture of red phosphorus, glue and ground glass. The glass powder is used to increase the friction.
Phosphorus explosion

Chemical element with the symbol P and atomic number 15.

- Phosphorus
White phosphorus exposed to air glows in the dark

73 related topics

Alpha

The Space Shuttle Main Engine burnt hydrogen with oxygen, producing a nearly invisible flame at full thrust.

Hydrogen

Chemical element with the symbol H and atomic number 1.

Chemical element with the symbol H and atomic number 1.

The Space Shuttle Main Engine burnt hydrogen with oxygen, producing a nearly invisible flame at full thrust.
Depiction of a hydrogen atom with size of central proton shown, and the atomic diameter shown as about twice the Bohr model radius (image not to scale)
Hydrogen gas is colorless and transparent, here contained in a glass ampoule.
Phase diagram of hydrogen. The temperature and pressure scales are logarithmic, so one unit corresponds to a 10x change. The left edge corresponds to 105 Pa, which is about atmospheric pressure.
A sample of sodium hydride
Hydrogen discharge (spectrum) tube
Deuterium discharge (spectrum) tube
Antoine-Laurent de Lavoisier
Hydrogen emission spectrum lines in the visible range. These are the four visible lines of the Balmer series
NGC 604, a giant region of ionized hydrogen in the Triangulum Galaxy
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The symbols D and T (instead of and ) are sometimes used for deuterium and tritium, but the symbol P is already in use for phosphorus and thus is not available for protium.

A farmer spreading manure to improve soil fertility

Fertilizer

Any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients.

Any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients.

A farmer spreading manure to improve soil fertility
World population supported with and without synthetic nitrogen fertilizers.
Founded in 1812, Mirat, producer of manures and fertilizers, is claimed to be the oldest industrial business in Salamanca (Spain).
Six tomato plants grown with and without nitrate fertilizer on nutrient-poor sand/clay soil. One of the plants in the nutrient-poor soil has died.
Inorganic fertilizer use by region
Total nitrogenous fertilizer consumption per region, measured in tonnes of total nutrient per year.
An apatite mine in Siilinjärvi, Finland.
Compost bin for small-scale production of organic fertilizer
A large commercial compost operation
Applying superphosphate fertilizer by hand, New Zealand, 1938
Fertilizer burn
N-Butylthiophosphoryltriamide, an enhanced efficiency fertilizer.
Fertilizer use (2018). From FAO's World Food and Agriculture – Statistical Yearbook 2020
The diagram displays the statistics of fertilizer consumption in western and central European counties from data published by The World Bank for 2012.
Runoff of soil and fertilizer during a rain storm
Large pile of phosphogypsum waste near Fort Meade, Florida.
Red circles show the location and size of many dead zones.
Global methane concentrations (surface and atmospheric) for 2005; note distinct plumes

For most modern agricultural practices, fertilization focuses on three main macro nutrients: Nitrogen (N), Phosphorus (P), and Potassium (K) with occasional addition of supplements like rock dust for micronutrients.

Daniel Rutherford, discoverer of nitrogen

Nitrogen

Chemical element with the symbol N and atomic number 7.

Chemical element with the symbol N and atomic number 7.

Daniel Rutherford, discoverer of nitrogen
The shapes of the five orbitals occupied in nitrogen. The two colours show the phase or sign of the wave function in each region. From left to right: 1s, 2s (cutaway to show internal structure), 2px, 2py, 2pz.
Table of nuclides (Segrè chart) from carbon to fluorine (including nitrogen). Orange indicates proton emission (nuclides outside the proton drip line); pink for positron emission (inverse beta decay); black for stable nuclides; blue for electron emission (beta decay); and violet for neutron emission (nuclides outside the neutron drip line). Proton number increases going up the vertical axis and neutron number going to the right on the horizontal axis.
Molecular orbital diagram of dinitrogen molecule, N2. There are five bonding orbitals and two antibonding orbitals (marked with an asterisk; orbitals involving the inner 1s electrons not shown), giving a total bond order of three.
Solid nitrogen on the plains of Sputnik Planitia on Pluto next to water ice mountains
Structure of [Ru(NH3)5(N2)]2+ (pentaamine(dinitrogen)ruthenium(II)), the first dinitrogen complex to be discovered
Mesomeric structures of borazine, (–BH–NH–)3
Standard reduction potentials for nitrogen-containing species. Top diagram shows potentials at pH 0; bottom diagram shows potentials at pH 14.
Nitrogen trichloride
Nitrogen dioxide at −196 °C, 0 °C, 23 °C, 35 °C, and 50 °C. converts to colourless dinitrogen tetroxide at low temperatures, and reverts to  at higher temperatures.
Fuming nitric acid contaminated with yellow nitrogen dioxide
Schematic representation of the flow of nitrogen compounds through a land environment
A container vehicle carrying liquid nitrogen.

Thus, despite nitrogen's position at the head of group 15 in the periodic table, its chemistry shows huge differences from that of its heavier congeners phosphorus, arsenic, antimony, and bismuth.

The chemical elements ordered in the periodic table

Chemical element

A chemical element refers to all aspects of the species of atoms that have a certain number of protons in their nuclei, including the pure substance consisting only of that species.

A chemical element refers to all aspects of the species of atoms that have a certain number of protons in their nuclei, including the pure substance consisting only of that species.

The chemical elements ordered in the periodic table
Estimated distribution of dark matter and dark energy in the universe. Only the fraction of the mass and energy in the universe labeled "atoms" is composed of chemical elements.
Periodic table showing the cosmogenic origin of each element in the Big Bang, or in large or small stars. Small stars can produce certain elements up to sulfur, by the alpha process. Supernovae are needed to produce "heavy" elements (those beyond iron and nickel) rapidly by neutron buildup, in the r-process. Certain large stars slowly produce other elements heavier than iron, in the s-process; these may then be blown into space in the off-gassing of planetary nebulae
Abundances of the chemical elements in the Solar System. Hydrogen and helium are most common, from the Big Bang. The next three elements (Li, Be, B) are rare because they are poorly synthesized in the Big Bang and also in stars. The two general trends in the remaining stellar-produced elements are: (1) an alternation of abundance in elements as they have even or odd atomic numbers (the Oddo-Harkins rule), and (2) a general decrease in abundance as elements become heavier. Iron is especially common because it represents the minimum energy nuclide that can be made by fusion of helium in supernovae.
Mendeleev's 1869 periodic table: An experiment on a system of elements. Based on their atomic weights and chemical similarities.
Dmitri Mendeleev
Henry Moseley

The composition of the human body, by contrast, more closely follows the composition of seawater—save that the human body has additional stores of carbon and nitrogen necessary to form the proteins and nucleic acids, together with phosphorus in the nucleic acids and energy transfer molecule adenosine triphosphate (ATP) that occurs in the cells of all living organisms.

Violet iodine vapour in a flask.

Iodine

Chemical element with the symbol I and atomic number 53.

Chemical element with the symbol I and atomic number 53.

Violet iodine vapour in a flask.
I2•PPh3 charge-transfer complexes in CH2Cl2. From left to right: (1) I2 dissolved in dichloromethane – no CT complex. (2) A few seconds after excess PPh3 was added – CT complex is forming. (3) One minute later after excess PPh3 was added, the CT complex [Ph3PI]+I− has been formed. (4) Immediately after excess I2 was added, which contains [Ph3PI]+[I3]−.
Structure of solid iodine
Iodine monochloride
Structure of iodine pentoxide
Structure of the oxidising agent 2-iodoxybenzoic acid
Testing a seed for starch with a solution of iodine
Diatrizoic acid, an iodine-containing radiocontrast agent
The thyroid system of the thyroid hormones T3 and T4
Comparison of the iodine content in urine in France (in microgramme/day), for some regions and departments (average levels of urine iodine, measured in micrograms per liter at the end of the twentieth century (1980 to 2000))

Phosphorus can reduce elemental iodine to hydroiodic acid, which is a reagent effective for reducing ephedrine or pseudoephedrine to methamphetamine.

Phosphoric acid speciation

Phosphate

Anion, salt, functional group or ester derived from a phosphoric acid.

Anion, salt, functional group or ester derived from a phosphoric acid.

Phosphoric acid speciation
Phosphate mine near Flaming Gorge, Utah, US, 2008
Train loaded with phosphate rock, Métlaoui, Tunisia, 2012
Sea surface phosphate from the World Ocean Atlas
Relationship of phosphate to nitrate uptake for photosynthesis in various regions of the ocean. Note that nitrate is more often limiting than phosphate. See the Redfield ratio.
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The phosphate ion has a molar mass of 94.97 g/mol, and consists of a central phosphorus atom surrounded by four oxygen atoms in a tetrahedral arrangement.

Eutrophication

Process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus.

Process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus.

1. Excess nutrients are applied to the soil. 2. Some nutrients leach into the soil and later drain into surface water. 3. Some nutrients run off over the ground into the body of water.  4. The excess nutrients cause an algal bloom.  5. The algal bloom reduces light penetration. 6. The plants beneath the algal bloom die because they cannot get sunlight to perform photosynthesis.  7. Eventually, the algal bloom dies and sinks to the bottom of the lake. Bacterial communities begin to decompose the remains, using up oxygen for respiration.  8. The decomposition causes the water to become depleted of oxygen if the water body is not regularly mixed vertically. Larger life forms, such as fish die.
Sodium triphosphate, once a component of many detergents, was a major contributor to eutrophication.
Cultural eutrophication is caused by human additions of nutrients into the water that cause over growth of algae which can block light and air exchange. The algae eventually are broken down by bacteria causing anoxic conditions and "dead zones".
Aerial view of Lake Valencia experiencing a large cultural eutrophication flux due to untreated wastewater discharging into the lake.
Eutrophication is apparent as increased turbidity in the northern part of the Caspian Sea, imaged from orbit.
Map of measured Gulf hypoxia zone, July 25–31, 2021-LUMCON-NOAA
Oxygen minimum zones (OMZs) (blue) and areas with coastal hypoxia (red) in the world’s ocean.
Eutrophication in a canal
The eutrophication of the Mono Lake which is a cyanobacteria-rich Soda lake.
Application of a phosphorus sorbent to a lake - The Netherlands

Nutrient pollution, a form of water pollution, is a primary cause of eutrophication of surface waters, in which excess nutrients, usually nitrogen or phosphorus, stimulate algal and aquatic plant growth.

Molar volume vs. pressure for α iron at room temperature

Iron

Chemical element with symbol Fe and atomic number 26.

Chemical element with symbol Fe and atomic number 26.

Molar volume vs. pressure for α iron at room temperature
Low-pressure phase diagram of pure iron
Magnetization curves of 9 ferromagnetic materials, showing saturation. 1.Sheet steel, 2.Silicon steel, 3.Cast steel, 4.Tungsten steel, 5.Magnet steel, 6.Cast iron, 7.Nickel, 8.Cobalt, 9.Magnetite
A polished and chemically etched piece of an iron meteorite, believed to be similar in composition to the Earth's metallic core, showing individual crystals of the iron-nickel alloy (Widmanstatten pattern)
Ochre path in Roussillon.
Banded iron formation in McKinley Park, Minnesota.
Pourbaix diagram of iron
Hydrated iron(III) chloride (ferric chloride)
Comparison of colors of solutions of ferrate (left) and permanganate (right)
Blue-green iron(II) sulfate heptahydrate
The two enantiomorphs of the ferrioxalate ion
Crystal structure of iron(II) oxalate dihydrate, showing iron (gray), oxygen (red), carbon (black), and hydrogen (white) atoms.
Blood-red positive thiocyanate test for iron(III)
Iron penta- carbonyl
Prussian blue
Iron harpoon head from Greenland. The iron edge covers a narwhal tusk harpoon using meteorite iron from the Cape York meteorite, one of the largest iron meteorites known.
The symbol for Mars has been used since antiquity to represent iron.
The iron pillar of Delhi is an example of the iron extraction and processing methodologies of early India.
Iron sickle from Ancient Greece.
Coalbrookdale by Night, 1801. Blast furnaces light the iron making town of Coalbrookdale.
"Gold gab ich für Eisen" – "I gave gold for iron". German-American brooch from WWI.
Iron powder
Iron furnace in Columbus, Ohio, 1922
17th century Chinese illustration of workers at a blast furnace, making wrought iron from pig iron
How iron was extracted in the 19th century
This heap of iron ore pellets will be used in steel production.
A pot of molten iron being used to make steel
Iron-carbon phase diagram
Photon mass attenuation coefficient for iron.
Structure of Heme b; in the protein additional ligand(s) would be attached to Fe.
A heme unit of human carboxyhemoglobin, showing the carbonyl ligand at the apical position, trans to the histidine residue

Pig iron has 3.5–4.5% carbon and contains varying amounts of contaminants such as sulfur, silicon and phosphorus.

Wet process flow diagram of phosphoric acid production. CW - cooling water.

Phosphoric acid

Inorganic compound with the chemical formula H3PO4.

Inorganic compound with the chemical formula H3PO4.

Wet process flow diagram of phosphoric acid production. CW - cooling water.

To produce food-grade phosphoric acid, phosphate ore is first reduced with coke in an electric arc furnace, to give elemental phosphorus.

Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in crystalline structure.

Allotropy

Property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements.

Property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements.

Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in crystalline structure.
Phase diagram of the actinide elements.

Other elements do not maintain distinct allotropes in different physical phases; for example, phosphorus has numerous solid allotropes, which all revert to the same P4 form when melted to the liquid state.